Bought a bad bike need help

So I have been shopping for a bike. Ended up with a trek 7.3fx. Seemed like a great overall bike as all I am doing is commuting. First day I get it the chain has or developed a pinch/scratch in one of the pins which caused the chain to constantly jump on the rear gears. Go take it in and they replace the chain. Today I get it back and ride for maybe 1.5mins and as I am riding up hill I switch to a lower gear on the front gearset. Well the chain then lodges in between those gears and I almost go off the bike because of it. So now I have a chain that is wedged in between the gears and will not budge for anything. Looks like I will be taking it back but I think this time going to return the bike because this is just nuts.

What I need help in is being over weight, 245 6'1", am I the complete cause of these problems? I know I my weight does not help anything but now I am almost nervous to ride the bike in fear something else is going to break. Should I just have the fix it or should I return it and get a sturdier bikes? I feel like for $550 I can get something much sturdier. Any help would be really appreciated. Thanks.

Sheesh, I'm 6'1 aqnd 245 lbs! I have several bikes and they run purrrrfect. Roadies, mtn bikes, and a tandem. Sounds like you need a good shop mechanic. One of the reasons I started doing my own maintenacne and wheel builds.

I once had a Trek roadie that ran purrfect ($600). I upgraded to a better quality bike ($1800). Everytime I swithced to the small ring in front, the chain would fly off to the inside. Shop guys said I didn't know how to shift gears. Morons! I used my conversion gears in the back so I knew it wasn't me. Took it to another shop. Guy spotted the problem within 10 seconds. Fixed it within 3 minutes.

The chainline was set up as an mtb when it should have been lined up thru the front derailleur cage roadie style. Some sad mechanics out there. You need to find a good one even if it means going to another store.

Sounds to me like the tension is wrong on the cables. Maybe the limit screws are off if it goes to the inside near teh frame. IF it's between the rings, sounds like they thru on a narrow chain. Maybe a 10 or 9 speed on an 8 speed system? Seems like that would be the only way a chain could get stuck between rings (gears).

You need to let up on the pedals when your shifting or you will destroy chains, cogs, and chainrings. If you jammed the chain that tight, you were really mashing. Don't shift the front deraileur while climbing, get in the chainring you want ahead of time.
Your chain jumping in the back was probably just cable stretch, it will take a couple hundred miles for them to settle. Your bike is fine, just adjust the barrel adjuster on the shifter some if it starts that again. If you are unsure, take it to the LBS, but there is plenty of information on Park tool's website and Sheldon Brown's website to help you out.

May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view.
May your mountains rise into and above the clouds. -Edward Abbey

Thanks for all the helpful replies. I am going to pay more attention to shifting though I will say I was trying to be very careful with it this time just in case it was me. My big problem now is trying to figure out how to get that chain loose. I will definitely hold on to it longer and try and work out all my issues. Hopefully nothing got screwed up too bad this time around.

FYI-Back riding seriously for a couple months, been riding bikes all my life, and just had to replace my front crankset because of a 'shifting while climbing' incident. Now, my drivetrain was worn, and needed to be replaced anyway, and I am always careful about shifting when on an incline. It happens-I bent a tooth on my middle chainring.

Don't give up on your bike just yet! work the chain out, or have your lbs remove it, and check to make sure the chainrings are not bent, and have at it again!

So I have been shopping for a bike. Ended up with a trek 7.3fx. Seemed like a great overall bike as all I am doing is commuting. First day I get it the chain has or developed a pinch/scratch in one of the pins which caused the chain to constantly jump on the rear gears. Go take it in and they replace the chain. Today I get it back and ride for maybe 1.5mins and as I am riding up hill I switch to a lower gear on the front gearset. Well the chain then lodges in between those gears and I almost go off the bike because of it. So now I have a chain that is wedged in between the gears and will not budge for anything. Looks like I will be taking it back but I think this time going to return the bike because this is just nuts.

What I need help in is being over weight, 245 6'1", am I the complete cause of these problems? I know I my weight does not help anything but now I am almost nervous to ride the bike in fear something else is going to break. Should I just have the fix it or should I return it and get a sturdier bikes? I feel like for $550 I can get something much sturdier. Any help would be really appreciated. Thanks.

I would say that the front dérailleur isn't set up right, front triples can take a little time to set up correctly, some shops are very busy, and not checking everything they should. Have them fix it, then give it another shot.......

Remember, the upper part of the chain's loop is what's providing the motive force. The lower part is slack and requires the tensioner at the rear derailleur to keep it under control. Shifting the rear derailleur moves the slack part of the chain to another gear, while shifting the front requires moving the part that's under tension. Pedaling hard while trying to shift the front derailleur makes the shift difficult, and more prone to problems than shifting the rear derailleur under similar conditions.

As Mr. Beanz pointed out, this is probably a case of having a 9 speed chain on an 8 speed drivetrain. Poor shifting and adjustment should not wedge a chain between the chainrings if that is what has happened. An 8 speed chain can not fit between the chainrings.

Bad Bike

Infecto, I don't think you bought a bad bike. I have a 2006 Trek 7500 that I have put about 800 miles on. I have been riding about 40 -50 miles per ride, in Canyon areas ( up big hills , and down big hills and I have only had one problem with the chain lodging in between the front gears, and that was due to me being in the hardest gear, running down hill fast, then not shifting to get over a small rise, and I put all 290 lbs on the pedal, and wow was it scary when it jumped off the gear. I have not had the bike tuned, nor any flats or tweaked rims, so I think the Trek is a decent bike.
I'm looking for a good road bike to lighten up and bike further but will always keep the Trek.

Infecto, I don't think you bought a bad bike. I have a 2006 Trek 7500 that I have put about 800 miles on. I have been riding about 40 -50 miles per ride, in Canyon areas ( up big hills , and down big hills and I have only had one problem with the chain lodging in between the front gears, and that was due to me being in the hardest gear, running down hill fast, then not shifting to get over a small rise, and I put all 290 lbs on the pedal, and wow was it scary when it jumped off the gear. I have not had the bike tuned, nor any flats or tweaked rims, so I think the Trek is a decent bike.
I'm looking for a good road bike to lighten up and bike further but will always keep the Trek.

Glad to hear your Trek has preformed well for you. I am hoping to get a good number of miles on mine. I think the major problems are worked out at this point. So I am ready to get some riding in without any major problems.

Good for you! Some guys post problem threads over and over but won't leave their LBS cause the guys there are soo nice. Heck, 'NICE' never got my bike running smoothly!

Yeah it was worth it. They only charged me a few bucks for a tube and labor for installing it. Did not charge me for removing the chain and tweaking the gears a bit. Probably going to start going there from now on.